Method for recovery of valuable metals

Abstract

A method for recovery of valuable metals according to the present invention comprises the steps of: (S1) leaching a sulfate solution from a waste battery material; (S2) adding a phosphorus-based compound to the sulfate solution to precipitate aluminum phosphate; and (S3) solid-liquid separating the aluminum phosphate from the sulfate solution, wherein the concentration of metal sulfate contained in the sulfate solution is 90 g / L or more.

Description

Method for recovering valuable metals

[0001] The present invention relates to a method for recovering valuable metals, and more particularly, to a method for recovering valuable metals from waste batteries.

[0002] The recent expansion of the battery electric vehicle (BEV) market has led to an increase in demand for secondary batteries. Scrap of defective batteries or cathode materials generated during the secondary battery manufacturing process, as well as scrap of used secondary batteries, contain valuable metals such as nickel, cobalt, and manganese. Recently, active development is underway in technologies to recover and recycle these valuable metals within secondary batteries.

[0003] Valuable metals such as nickel, cobalt, and manganese can be recovered by dissolving secondary battery raw materials in acid and then using solvent extraction. Solvent extraction utilizes the principle that metal ions are extracted from an aqueous solution into an organic solvent. Typically, when recovering valuable metals from secondary battery raw materials using solvent extraction, a process is required to remove impurities contained in the raw materials. Representative examples of such impurities include aluminum and copper. However, the byproducts generated during the impurity removal process increase the waste rate of valuable metals, ultimately lowering the recovery rate.

[0004] The purpose of the present invention is to provide a method for recovering valuable metals from waste batteries, which can minimize the loss rate of valuable metals and increase the removal rate of aluminum while reducing the recovery time when recovering valuable metals from waste batteries.

[0005] A method for recovering valuable metals according to the present invention comprises a step (S1) of leaching a sulfate solution from a waste battery material, a step (S2) of adding a phosphorus compound to the sulfate solution to precipitate aluminum phosphate, and a step (S3) of separating the aluminum phosphate from the sulfate solution into solid and liquid, wherein the concentration of the metal sulfate contained in the sulfate solution is 90 g / L or more.

[0006] In the method for recovering valuable metals according to the present invention, the concentration of aluminum contained in the sulfate solution may be 1 g / L or more.

[0007] In the method for recovering valuable metals according to the present invention, the metal sulfate may be at least one sulfate selected from the group consisting of nickel, cobalt, manganese, lithium, copper, and aluminum.

[0008] In the method for recovering valuable metals according to the present invention, step (S1) may include a step of calcining crushed waste batteries without solvent treatment. Step (S1) may include a step of recovering lithium using deionized water without carbon dioxide.

[0009] In the step (S2) of the method for recovering valuable metals according to the present invention, the amount of the phosphorus compound added may be 0.1 wt% to 7.0 wt% relative to the weight of the sulfate solution.

[0010] In the method for recovering valuable metals according to the present invention, the molar ratio of phosphorus contained in the added phosphorus compound to aluminum contained in the sulfate solution (P / Al molar ratio) may be 0.92 to 1.72.

[0011] In the method for recovering valuable metals according to the present invention, the phosphorus compound may be sodium phosphate.

[0012] In the method for recovering valuable metals according to the present invention, the step (S2) may last for 2 to 8 hours. The step (S2) may be performed at a temperature of 25°C to 95°C. The pH of the sulfate solution in the step (S2) may be 2.0 to 5.0.

[0013] In the method for recovering valuable metals according to the present invention, at least 96.0% of the aluminum contained in the sulfate solution can be removed by precipitation as the aluminum phosphate, on a weight basis.

[0014] The method for recovering valuable metals according to the present invention may further include a step (S4) of removing phosphorus contained in the sulfate solution. In the step (S4), the pH of the sulfate solution may be 5.0 or higher.

[0015] Recently, there has been a trend toward reducing the process of separating and sorting aluminum thin films from spent batteries to increase the recovery rate of valuable metals contained in batteries. As a result, battery material raw materials extracted from spent batteries contain high concentrations of aluminum, which is an impurity. Conventionally, to remove aluminum, the aluminum contained in the leachate of battery raw materials was reacted with a hydroxide source, and the aluminum was precipitated and removed as a process byproduct in the form of aluminum hydroxide. However, when the leachate contained a high concentration of aluminum, the valuable metal to be recovered was precipitated in the form of a hydroxide salt when the hydroxide source was added, which resulted in a problem in that the recovery rate of the valuable metal was reduced.

[0016] To solve these problems, the present invention adds a phosphorus compound instead of a hydroxide source to a sulfate solution containing metal sulfate at a concentration of 90 g / L or more, thereby minimizing the loss rate of the metal to be recovered, increasing the removal rate of aluminum, and reducing the time required for the aluminum removal process even when the battery material raw material contains a high concentration of aluminum. As a result, the present invention has the advantage of being applicable to waste battery processing technology targeting medium and large-sized batteries in pack units by securing a variety of processable battery material raw materials, and being usable in the field of electric vehicles, etc.

[0017] Figure 1 is a process diagram of a method for recovering valuable metals according to the present invention.

[0018] Hereinafter, specific details for implementing the present disclosure will be described in detail with reference to the attached drawings. However, in the following description, specific descriptions of widely known functions or configurations will be omitted if they may unnecessarily obscure the gist of the present disclosure.

[0019] In the attached drawings, identical or corresponding components are assigned the same reference numerals. Furthermore, in the description of the embodiments below, duplicate descriptions of identical or corresponding components may be omitted. However, even if a description of a component is omitted, it is not intended that such component is not included in any embodiment.

[0020] The terms used in this disclosure will be briefly described, followed by a detailed description of the disclosed embodiments. The terms used in this specification have been selected from widely used, current terms, taking into account the functions of the present disclosure. However, these terms may vary depending on the intentions of engineers working in the relevant fields, precedents, the emergence of new technologies, etc. Furthermore, in certain cases, terms may be arbitrarily selected by the applicant, and in such cases, their meanings will be described in detail in the relevant description of the invention. Therefore, the terms used in this disclosure should not be defined simply as names of terms, but rather based on their meanings and the overall content of the present disclosure.

[0021] In this disclosure, singular expressions include plural expressions unless the context clearly specifies that they are singular. Furthermore, plural expressions include singular expressions unless the context clearly specifies that they are plural.

[0022] In this disclosure, when it is said that a part includes a certain component, this does not mean that other components are excluded, but rather that other components may be included, unless specifically stated otherwise.

[0023] In this disclosure, the description of “A and / or B” means A, or B, or A and B.

[0024] The advantages and features of the disclosed embodiments, and methods for achieving them, will become clearer with reference to the embodiments described below, along with the accompanying drawings. However, the present disclosure is not limited to the embodiments disclosed below and may be implemented in various different forms. These embodiments are provided solely to ensure the completeness of the disclosure and to fully inform those skilled in the art of the scope of the invention.

[0025] A method for recovering valuable metals according to the present invention includes a step (S1) of leaching a sulfate solution from a waste battery material, a step (S2) of adding a phosphorus compound to the sulfate solution to precipitate aluminum phosphate, and a step (S3) of solid-liquid separating aluminum phosphate from the sulfate solution, wherein the concentration of metal sulfate contained in the sulfate solution is 90 g / L or more.

[0026] Hereinafter, each step of the method for recovering valuable metals according to the present invention will be described in more detail with reference to the drawings. Fig. 1 is a process diagram of the method for recovering valuable metals according to the present invention. As illustrated in Fig. 1, the method for recovering valuable metals includes a step (S1) of leaching a sulfate solution from a waste battery material, a step (S2) of adding a phosphorus compound to the sulfate solution to precipitate aluminum phosphate, and a step (S3) of solid-liquid separating aluminum phosphate from the sulfate solution, and may further include a step (S4) of removing phosphorus contained in the sulfate solution.

[0027] Step of leaching sulfate solution from waste battery material (S1)

[0028] The method for recovering valuable metals according to the present invention begins with a step (S1) of leaching a sulfate solution from waste battery materials. For example, step (S1) may be a step of recovering waste battery materials and leaching a sulfate solution. Alternatively, step (S1) may be a step of leaching a sulfate solution from at least one selected from the group consisting of nickel ore, nickel MHP (Mixed Hydroxide Precipitate), and nickel oxide instead of waste battery materials.

[0029] Waste battery materials can be recovered through a pretreatment process. This pretreatment process may include a discharge process, a dismantling process, a crushing / pulverizing process, a drying process, and a calcination process.

[0030] The discharge process discharges the stored power in a spent battery to prevent explosions that may occur during subsequent processes. This process can be performed mechanically using a discharger or through brine discharge.

[0031] The dismantling process involves dismantling waste batteries into modules and / or cells. The dismantling process may be performed after the discharge process, but is not limited to this. The dismantling process may be performed first, followed by the discharge process. The dismantling process may be performed, for example, using automated dismantling equipment.

[0032] The shredding / crushing process involves crushing and pulverizing dismantled waste batteries, converting them into shredded powder. This process can be conducted under a nitrogen atmosphere while spraying water to prevent sparks and explosions. After crushing and pulverizing, the sprayed water and the electrolyte leaking from the waste batteries can be removed. For example, the water and electrolyte can be removed by centrifugation using a rotary barrel.

[0033] The drying process is intended to remove water and electrolytes remaining after the crushing / grinding process. For example, the drying process can be performed by applying nitrogen gas heated to approximately 50°C or higher to a dryer containing the crushed powder.

[0034] The sintering process is a process for roasting crushed / pulverized batteries. Typically, sintering, metal oxide injection, and binder addition are performed during the manufacturing process of cathode materials to improve battery performance. As a result, spent battery materials, including cathode materials, may contain various oxide-type valuable metals and impurities, which can hinder the recovery of valuable metals through recycling of spent batteries. To remove these impurities, sintering can be performed at high temperatures. The sintering process can be a process for reducing and roasting crushed / pulverized batteries in an inert gas atmosphere (IAR: Inert Atmospheric Roaster). For example, the sintering process can reduce and roast crushed / pulverized batteries in a nitrogen atmosphere at a temperature of 800°C to 900°C for 1 to 3 hours.

[0035] The sintering process of the present invention can omit a separate solvent treatment for removing the binder contained in the waste battery material. Since the binder can be removed by sintering the waste battery in a reducing atmosphere without a separate solvent treatment in the sintering process, the sintering process can be simplified. In addition, in the sintering process of the present invention, metallic substances in the form of oxides combined with oxygen in the waste battery can be reduced. Specifically, in the process of reducing and sintering the shredded / pulverized battery, some high-oxide compounds (Me2O3, Me=Ni, Co, Mn) can be reduced to low-oxide compounds (MeO, Me=Ni, Co, Mn), and as a result, the amount of auxiliary materials (H2O2, hydrogen peroxide) used during the sulfate solution leaching can be reduced.

[0036] Meanwhile, the waste battery material may be, but is not limited to, waste battery scrap, black mass processed into raw materials through a recycling process from waste batteries, waste cathode material generated during the cathode material manufacturing process, or a combination thereof.

[0037] The waste battery material may include one or more metal oxides. For example, the metal oxide included in the waste battery material may be at least one selected from the group consisting of lithium cobalt oxide (LiCoO2), lithium nickel cobalt manganese oxide (LiNiCoMnO2), lithium manganese oxide (LiMnO2), and lithium iron phosphate oxide (LiFePO4).

[0038] In step (S1), a sulfate solution can be extracted from the waste battery material through a wet process. For example, the sulfate solution may be extracted from the waste battery material recovered through the aforementioned pretreatment process. A small amount of reducing agent may be added during the sulfate solution extraction to improve the dissolution rate of the cake. Hydrogen peroxide (H2O2) may be used as the reducing agent.

[0039] According to one embodiment of the present invention, step (S1) can be performed through a pre-separation process and a leaching process.

[0040] The pre-separation process is a process of leaching lithium (Li) from crushed / pulverized waste batteries by adding water to the waste batteries and pre-separating them. For example, in the lithium pre-separation process, the crushed batteries are dissolved in water, and the lithium (Li) solution is leached at 10°C to 30°C for 1 to 3 hours to produce a lithium carbonate (Li2CO3) solution, and the cake is separated. When a sulfate solution is leached from the cake from which lithium is pre-separated from waste battery materials, the amount of auxiliary materials such as hydrogen peroxide can be minimized, and stable process management in a continuous process is possible. In the pre-separation process of the present invention, lithium can be recovered using deionized water without carbon dioxide (CO2). When lithium is recovered using only deionized water without using carbon dioxide (CO2), the process cost can be reduced and the carbon footprint can be reduced.

[0041] The leaching process is a process for leaching a sulfate solution from the cake produced from the pre-separation process. Specifically, in the leaching process, the cake produced from the pre-separation process can be reduced and leached with sulfuric acid and hydrogen peroxide (H2O2) at 80°C to 85°C for 1 to 8 hours.

[0042] Meanwhile, the metal sulfate contained in the sulfate solution may be one or more sulfates selected from the group consisting of nickel, cobalt, manganese, lithium, copper, and aluminum.

[0043] The concentration of the metal sulfate contained in the sulfate solution may be 90 g / L or more, specifically 90 g / L to 140 g / L, and more specifically 90 g / L to 120 g / L. When the concentration of the metal sulfate is less than 90 g / L, the reaction efficiency of the metal sulfate when removing impurities contained in the sulfate solution decreases, thereby lowering the loss rate of the valuable metal to be recovered from the metal sulfate. However, since the recovery amount of the valuable metal decreases due to the relatively low concentration of the metal sulfate, there is a problem that the time required to recover a certain amount or more of the valuable metal through waste battery recycling becomes longer.

[0044] The concentration of aluminum contained in the sulfate solution may be 1 g / L or more, specifically 3 g / L or more, and more specifically 3 g / L to 10 g / L. When aluminum is contained in the sulfate solution at a high concentration such as the above numerical range, there is a problem that when a hydroxide source is added to remove aluminum, the valuable metal to be recovered is precipitated in the form of a hydroxide salt, thereby reducing the recovery rate of the valuable metal. On the other hand, when a phosphorus compound is added instead of a hydroxide source to remove aluminum, as in step (S2) described below, the removal rate of aluminum can be increased while minimizing the loss rate of the valuable metal to be recovered.

[0045] Step (S2) of precipitating aluminum phosphate by adding a phosphorus compound to a sulfate solution

[0046] Step (S2) is a process for removing aluminum (Al), an impurity, from the leached sulfate solution. Specifically, in step (S2), a phosphorus compound may be added to the leached sulfate solution to precipitate aluminum phosphate.

[0047] The amount of the phosphorus compound added may be 0.1 wt% to 7.0 wt%, specifically 0.3 wt% to 5.0 wt%, and more specifically 0.3 wt% to 4.8 wt%, relative to the weight of the sulfate solution. When the weight ratio of the added phosphorus compound relative to the weight of the sulfate solution satisfies the above numerical range, the problem of the efficiency and economic feasibility of the process being lowered due to the increase in the input amount of the phosphorus compound and the increase in the liquid volume of the entire process resulting in an increase in the size of the process equipment can be prevented.

[0048] The molar ratio of phosphorus (P) contained in the added phosphorus compound to aluminum (Al) contained in the sulfate solution (P / Al molar ratio) may be 0.92 to 1.72, specifically 0.92 to 1.49, and more specifically 1.15 to 1.49. When the molar ratio of phosphorus to aluminum satisfies the above numerical range, there is an effect of lowering the concentration of phosphorus (P) contained in the sulfate solution to 5 ppm or less after the precipitation reaction.

[0049] The phosphorus compound may be at least one selected from the group consisting of sodium phosphate (Na3PO4) and phosphoric acid (H3PO4), but is not limited thereto. Preferably, the phosphorus compound according to the present invention may be sodium phosphate. When sodium phosphate is added to remove aluminum contained in a sulfate solution, the amount of neutralizing agent input is significantly reduced because no free acid is generated in the aluminum phosphate precipitation reaction. In addition, sodium phosphate is relatively inexpensive compared to other phosphorus compounds. As a result, when the method for recovering valuable metals of the present invention is applied to a waste battery recycling technology, the process time and cost can be significantly reduced.

[0050] (S2) In step, aluminum can be precipitated as an aluminum phosphate (AlPO4) compound through a reaction such as [Reaction Scheme 1] or [Reaction Scheme 2] below.

[0051] [Reaction Formula 1]

[0052] Al2(SO4)3+ 2Na3PO4-> 2AlPO4↓ + 3Na2SO4

[0053] [Reaction Formula 2]

[0054] Al2(SO4)3+ 2H3PO4+ 6NaOH -> 2AlPO4↓+ 3Na2SO4+ 6H2O

[0055] (S2) Step may last for 2 to 8 hours, specifically 2 to 6 hours, and more specifically 2 to 4 hours. When the duration of step (S2) satisfies the above numerical range, the loss rate of valuable metals in the sulfate solution can be reduced while the removal rate of aluminum, which is an impurity, can be increased.

[0056] (S2) Step can be performed at a temperature of 25°C to 95°C, specifically 45°C to 95°C, and more specifically 60°C to 90°C. When the temperature in step (S2) satisfies the above numerical range, the removal rate of aluminum can be increased without increasing the loss rate of valuable metals in the sulfate solution.

[0057] (S2) The pH of the sulfate solution may be 2.0 to 5.0, specifically 2.0 to 3.5, and more specifically 2.5 to 3.5. When the pH of the sulfate solution in step (S2) satisfies the above numerical range, the removal rate of aluminum can be increased while preventing the problem of nickel loss rate increasing due to nickel precipitation as a compound in the sulfate solution.

[0058] In step (S2), at least 96.0%, specifically at least 97.0%, and more specifically at least 98.0% of the aluminum contained in the sulfate solution, by weight, can be removed by precipitation as aluminum phosphate. Accordingly, by sufficiently removing aluminum from the sulfate solution, the impurity content in the recovered valuable metal can be significantly reduced.

[0059] Step (S3) of separating the aluminum phosphate from the sulfate solution.

[0060] Step (S3) is a step for separating the aluminum phosphate and sulfate solution precipitated in step (S2). Specifically, step (S3) can recover the precipitated aluminum phosphate and distribute and separate the sulfate solution. The sulfate solution separated and recovered by step (S3) can be a solution from which aluminum has been removed and which contains the valuable metal to be recovered.

[0061] The sulfate solution filtered by step (S3) can be sent to a phosphorus removal process (e.g., step (S4)), and the precipitated aluminum phosphate can be discarded or stored separately.

[0062] Step for removing phosphorus contained in sulfate solution (S4)

[0063] Step (S4) is a step for removing phosphorus (P) remaining in the sulfate solution. Specifically, step (S4) is a process for removing phosphorus by adding aluminum sulfate (Al2(SO4)3) to the sulfate solution that has gone through steps (S1) to (S3). For example, by adding aluminum sulfate and sodium hydroxide (NaOH) to the sulfate solution to adjust the pH to 5.0 or higher, specifically to pH 5 to 6, and reacting at 50°C to 70°C for 4 to 8 hours, phosphorus contained in the sulfate solution can be precipitated and removed, and iron (Fe) and other impurities can also be coprecipitated and removed.

[0064] Although some of the valuable metals to be recovered are precipitated together as residue in step (S4), loss of the valuable metals may not occur in step (S4) by reintroducing the precipitates into the spent battery material in step (S1).

[0065] (S4) The pH of the sulfate solution in step (S4) may be 5 or higher, specifically 5 to 6, and more specifically 5.5 to 6. When the pH of the sulfate solution in step (S4) satisfies the above numerical range, aluminum (Al) added in excess relative to phosphorus (P) can be removed by precipitation in the form of aluminum hydroxide (Al(OH)3).

[0066] Meanwhile, in the present invention, after the steps (S1), (S2) and (S3), and additionally the step (S4), the valuable metal can be recovered from the sulfate solution through a conventional method such as a solvent extraction method.

[0067] Hereinafter, embodiments of the present invention will be described in detail so that those skilled in the art can easily implement them. However, the present invention may be implemented in various different forms and is not limited to the embodiments described herein.

[0068] Examples and Comparative Examples

[0069] Example 1

[0070] In Example 1, valuable metals were recovered from spent batteries through the aforementioned steps. Detailed conditions for each step are as follows.

[0071] (S1) Step

[0072] According to the pretreatment process, the spent battery materials were recovered through the discharge process, dismantling process, crushing / pulverizing process, drying process, and calcination process. The sulfate solution was extracted from the recovered spent battery materials through a wet process. The wet process was carried out in the order of the pre-separation process and the leaching process. In the pre-separation process, water at 25℃ was added to the spent battery materials that had gone through the calcination process, and leaching was performed for 2 hours. In the leaching process, lithium was pre-separated in the pre-separation process, and sulfuric acid and 30% hydrogen peroxide (H2O2) were added to the resulting cake, and leaching was performed at 80℃ for 8 hours based on pH 3.0. At this time, the concentration of metal sulfate contained in the leached sulfate solution was 90 g / L, and the concentration of aluminum was 1 g / L.

[0073] (S2) Step

[0074] (S1) Sodium phosphate (Na3PO4) was added to the sulfate solution extracted through step 1, and sodium hydroxide (NaOH) was added to adjust the pH. The amount of sodium phosphate added was 2.5 wt% based on the weight of the sulfate solution. Afterwards, the reaction was performed for 4 hours at 85°C and the pH of the sulfate solution was 3 to precipitate aluminum phosphate.

[0075] (S3) Step

[0076] (S2) The precipitated aluminum phosphate and sulfate solution were separated using a solid-liquid separator or centrifuge.

[0077] Example 2

[0078] Valuable metals were recovered in the same manner as in Example 1, except that the concentration of aluminum in the sulfate solution was 8 g / L.

[0079] Example 3

[0080] Valuable metals were recovered in the same manner as in Example 1, except that the concentration of aluminum in the sulfate solution was 8 g / L and the pH of the sulfate solution was 4.

[0081] Example 4

[0082] Valuable metals were recovered in the same manner as in Example 1, except that the concentration of aluminum in the sulfate solution was 8 g / L and the pH of the sulfate solution was 5.

[0083] Example 5

[0084] Valuable metals were recovered in the same manner as in Example 1, except that phosphoric acid (H3PO4) was added instead of sodium phosphate (Na3PO4) to the sulfate solution.

[0085] Example 6

[0086] Valuable metals were recovered in the same manner as in Example 1, except that phosphoric acid (H3PO4) was added instead of sodium phosphate (Na3PO4) to the sulfate solution and the concentration of aluminum in the sulfate solution was 8 g / L.

[0087] Comparative Example 1

[0088] Valuable metals were recovered in the same manner as in Example 1, except that only sodium hydroxide (NaOH) was added instead of sodium phosphate (Na3PO4) and sodium hydroxide (NaOH) to the sulfate solution, and that the pH of the sulfate solution was 5.

[0089] Comparative Example 2

[0090] Valuable metals were recovered in the same manner as in Comparative Example 1, except that the concentration of aluminum in the sulfate solution was 3 g / L.

[0091] Comparative Example 3

[0092] Valuable metals were recovered in the same manner as in Comparative Example 1, except that the concentration of aluminum in the sulfate solution was 5 g / L.

[0093] Comparative Example 4

[0094] Valuable metals were recovered in the same manner as in Comparative Example 1, except that the concentration of aluminum in the sulfate solution was 8 g / L.

[0095] Comparative Example 5

[0096] Valuable metals were recovered in the same manner as in Example 1, except that the concentration of metal sulfate in the sulfate solution was 60 g / L, the concentration of aluminum was 5 g / L, and the pH of the sulfate solution was 3.

[0097] Experimental Example 1: Measurement of loss / recovery rates and response times at stage S2.

[0098] In each S2 step of the examples and comparative examples, the loss rate of valuable metals (Ni, Co, Mn), the recovery rate of impurities (Al), and the reaction time were measured and shown in Tables 1 and 2 below.

[0099] The loss rate of valuable metal and the recovery rate of impurities refer to the values ​​calculated by excluding the loss in the process of recovering the target metal (e.g., Ni) in a commercial form (e.g., NiSO4). At this time, the weight of the raw material (and slag) containing the target metal was measured using a balance, and the concentration of the metal in the form of a leached compound was measured using ICP-AES spectroscopic analysis, and the loss rate of each metal and the recovery rate of impurities were calculated from the results.

[0100] The reaction time of step S2 was measured as the time elapsed from the time the feed was added to the sulfate solution until the precipitation reaction no longer occurred.

[0101] Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Metal sulfate concentration (g / L) 90 90 90 90 90 90 Aluminum concentration (g / L) 188 818 Type of input material Na3PO4+ NaOHNa3PO4+ NaOHNa3PO4+ NaOHNa3PO4+ NaOHH3PO4+ NaOHH3PO4+ NaOHS2 pH of sulfate solution 334 533 Ni loss (%) 0.11 0.96 1.17 1.82 0.10 0.94 Co loss (%) 0.23 1.16 1.21 1.63 0.19 1.49 Mn loss (%) 0.4 11.17 1.67 2.42 0.36 1.99 Al recovery (%)96.799.199.799.896.699.0S2 Step Duration (hr)444444

[0102] Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Metal sulfate concentration (g / L) 90 90 90 90 60 Aluminum concentration (g / L) 13 588 Type of input NaOH NaOH NaOH NaOH Na3 PO4 + NaOH S2 pH of sulfate solution in step 5 55 53 Ni loss rate (%) 1.47 5.59 10.91 8.30.91 Co loss rate (%) 1.08 1.78 4.47 10.8 0.22 Mn loss rate (%) 0.26 1.42 1.73 8.69 0.34 Al recovery rate (%) 91.99 7.09 8.29 9.09 9.2 Time required for S2 step (hr) 88 812

[0103] According to Tables 1 and 2, in the case of Examples 1 to 6 in which a phosphorus compound was added while the concentration of metal sulfate in the sulfate solution was 90 g / L or more, compared to Comparative Examples 1 to 4 in which a hydroxide source was added instead of the phosphorus compound, it can be confirmed that the loss rates of nickel, cobalt, and manganese were lower, the recovery rate (removal rate) of aluminum was higher, and the time required for the S2 step was reduced. In addition, in the case of Examples 1 to 6, it can be confirmed that the time required for the S2 step was significantly reduced compared to Comparative Example 5 in which the concentration of metal sulfate was less than 90 g / L.

[0104] While the present invention has been described in connection with certain embodiments herein, it should be understood that various modifications and variations can be made without departing from the spirit and scope of the invention, as understood by those skilled in the art. Furthermore, such modifications and variations are intended to fall within the scope of the claims appended to this specification.

[0105] Anyone having ordinary skill in the art to which the present invention pertains can make various substitutions, modifications, and changes within the scope that does not depart from the technical spirit of the present invention, and therefore the present invention is not limited to the above-described embodiments and the attached drawings.

Claims

1. (S1) A step of leaching a sulfate solution from a waste battery material; (S2) a step of adding a phosphorus compound to the above sulfate solution to precipitate aluminum phosphate; and (S3) comprising a step of separating the aluminum phosphate from the sulfate solution, A method for recovering valuable metals, wherein the concentration of metal sulfate contained in the above sulfate solution is 90 g / L or more.

2. In paragraph 1, A method for recovering valuable metals, wherein the concentration of aluminum contained in the above sulfate solution is 1 g / L or more.

3. In paragraph 1, A method for recovering valuable metals, wherein the metal sulfate is at least one sulfate selected from the group consisting of nickel, cobalt, manganese, lithium, copper and aluminum.

4. In paragraph 1, The above step (S1) is: A method for recovering valuable metals, comprising a step of calcining crushed waste batteries without solvent treatment.

5. In paragraph 1, The above step (S1) is: A method for recovering valuable metals, comprising the step of recovering lithium using deionized water without carbon dioxide.

6. In paragraph 1, In the above step (S2), A method for recovering valuable metals, wherein the amount of the above-mentioned phosphorus compound added is 0.1 wt% to 7.0 wt% relative to the weight of the above-mentioned sulfate solution.

7. In paragraph 1, A method for recovering valuable metals, wherein the molar ratio of phosphorus contained in the added phosphorus compound to aluminum contained in the sulfate solution (P / Al molar ratio) is 0.92 to 1.

72.

8. In paragraph 1, A method for recovering valuable metals, wherein the above-mentioned phosphorus compound is sodium phosphate.

9. In paragraph 1, A method for recovering valuable metals, wherein the step (S2) lasts for 2 to 8 hours.

10. In paragraph 1, A method for recovering valuable metals, wherein the step (S2) is performed at a temperature of 25°C to 95°C.

11. In paragraph 1, A method for recovering valuable metals, wherein the pH of the sulfate solution in the step (S2) is 2.0 to 5.

0.

12. In paragraph 1, A method for recovering valuable metals, wherein 96.0% or more of the aluminum contained in the sulfate solution is precipitated and removed as aluminum phosphate, by weight.

13. In paragraph 1, (S4) A method for recovering valuable metals, further comprising a step of removing phosphorus contained in the sulfate solution.

14. In paragraph 13, A method for recovering valuable metals, wherein the pH of the sulfate solution in the step (S4) is 5.0 or higher.

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